Ambulance

NEW
Advancing Acute Pain Management
At last, PENTHROX ® is here...
Fast, effective pain management designed
for fast, efficient patient management.
PENTHROX is indicated for the emergency relief of moderate to severe pain in
conscious adult patients with trauma and associated pain 1
Now there’s a new PCA * in a lightweight, portable, handheld inhaler for emergency relief of moderate
to severe pain in conscious adults with trauma. With minimal set-up and no need for cylinders, cannulas
or mandatory opioid-related A&E attendances, PENTHROX offers you the potential to reduce
dedicated treatment time and improve patient management.
PENTHROX 3mL inhalation vapour, liquid: Please refer to the Summary of Product Characteristics (SPC) before
prescribing. Abbreviated Prescribing Information. Presentation: Each vial of PENTHROX contains 3mL of methoxyflurane
99.9%, a clear, almost colourless, volatile liquid, with a characteristic fruity odour. Each PENTHROX combination pack consists of
one 3mL bottle, one PENTHROX Inhaler and one Activated Carbon (AC) chamber. Indications: Emergency relief of moderate to
severe pain in conscious adult patients with trauma and associated pain. Dosage and administration: PENTHROX should be selfadministered
under supervision of a person trained in its administration, using the hand held PENTHROX Inhaler. Adults: One
bottle of 3mL PENTHROX to be vaporised in a PENTHROX Inhaler. On finishing the 3mL dose, another 3mL may be used. The dose
should not exceed 6mL in a single administration. Methoxyflurane may cause renal failure if the recommended dose is exceeded.
The lowest effective dosage to provide analgesia should be used. Onset of pain relief is rapid and occurs after 6-10 inhalations.
Patients are able to titrate the amount of PENTHROX inhaled and should be instructed to inhale intermittently to achieve adequate
analgesia. Continuous inhalation provides analgesic relief for up to 25-30 minutes; intermittent inhalation may provide longer
analgesic relief. Administration on consecutive days is not recommended and the total dose to a patient in a week should not
exceed 15mL. Children: PENTHROX should not be used in children under 18 years. For detailed information on the method of
administration refer to the SPC. Contraindications: Use as an anaesthetic agent. Hypersensitivity to PENTHROX or any fluorinated
anaesthetic. Patients with known or genetically susceptible to malignant hyperthermia or a history of severe adverse reactions in
either patient or relatives. Patients who have a history of showing signs of liver damage after previous methoxyflurane use or
halogenated hydrocarbon anaesthesia. Clinically significant renal impairment. Altered level of consciousness due to any cause
including head injury, drugs or alcohol. Clinically evident cardiovascular instability. Clinically evident respiratory depression.
Warnings and Precautions: Methoxyflurane causes significant nephrotoxicity at high doses. Nephrotoxicity is also related to the
rate of metabolism. Factors that increase the rate of metabolism such as drugs that induce hepatic enzymes can increase the risk of
toxicity with methoxyflurane as well as sub-groups of people with genetic variations that may result in fast metaboliser status. The
lowest effective dose should be administered, especially in the elderly or patients with other known risk factors of renal disease.
Methoxyflurane should be cautiously used in patients with conditions that would pre-dispose to renal injury. Methoxyflurane is
metabolised in the liver, therefore increased exposures in patients with hepatic impairment can cause toxicity. PENTHROX should
be used with care in patients with underlying hepatic conditions or with risks for hepatic dysfunction. Previous exposure to
halogenated hydrocarbon anaesthetics (including methoxyflurane when used as an anaesthetic agent), especially if the interval is
less than 3 months, may increase the potential for hepatic injury. Cautious clinical judgement should be exercised when PENTHROX
is to be used more frequently than on one occasion every 3 months. Potential effects on blood pressure and heart rate are known
class-effects of high-dose methoxyflurane used in anaesthesia and other anaesthetics. Caution required in elderly due to possible
reduction in blood pressure. Potential CNS effects such as sedation, euphoria, amnesia, ability to concentrate, altered sensorimotor
co-ordination and change in mood are known class-effects. The CNS effects can be a risk factor for potential abuse. To reduce
occupational exposure to methoxyflurane, the PENTHROX Inhaler should always be used with the AC Chamber which adsorbs
exhaled methoxyflurane. Multiple use of PENTHROX Inhaler without the AC Chamber creates additional risk. Elevation of liver
enzymes, blood urea nitrogen and serum uric acid have been reported in exposed maternity ward staff when methoxyflurane was
used in the past at the time of labour and delivery. PENTHROX is not appropriate for providing relief of break-through pain/
exacerbations in chronic pain conditions or for the relief of trauma related pain in closely repeated episodes for the same patient.
Interactions: Methoxyflurane is metabolised by the CYP 450 enzymes, particularly CYP 2E1 and to some extent CYP 2A6. It is
possible that enzyme inducers (such as alcohol or isoniazid for CYP 2E1 and phenobarbital or rifampicin for CYP 2A6) which increase
the rate of methoxyflurane metabolism might increase its potential toxicity and they should be avoided concomitantly with
methoxyflurane. Concomitant use of PENTHROX with CNS depressants, such as opioids, sedatives or hypnotics, general
anaesthetics, phenothiazines, tranquillisers, skeletal muscle relaxants, sedating antihistamines and alcohol may produce additive
depressant effects. If opioids are given concomitantly with PENTHROX, the patient should be observed closely. Concomitant use
of methoxyflurane with medicines (eg contrast agents and some antibiotics) which are known to have a nephrotoxic effect should
be avoided as there may be an additive effect on nephrotoxicity; tetracycline, gentamicin, colistin, polymyxin B and amphotericin
B have known nephrotoxic potential. Sevoflurane anaesthesia should be avoided following methoxyflurane analgesia, as
sevoflurane increases serum fluoride levels and methoxyflurane nephrotoxicity is associated with raised serum fluoride. When
methoxyflurane was used for anaesthesia at the higher doses of 40–60mL, there were reports of drug interaction with hepatic
enzyme inducers (eg barbiturates) increasing metabolism of methoxyflurane and resulting in a few reported cases of nephrotoxicity;
reduction of renal blood flow and hence anticipated enhanced renal effect when used in combination with drugs (eg barbiturates)
reducing cardiac output; and class effect on cardiac depression, which may be enhanced by other cardiac depressant drugs, eg
intravenous practolol during cardiac surgery. Fertility, pregnancy and lactation: No clinical data on effects of methoxyflurane on
fertility are available. As with all medicines care should be exercised when administered during pregnancy especially the first
trimester. There is insufficient information on the excretion of methoxyflurane in human milk. Caution should be exercised when
methoxyflurane is administered to a nursing mother. Effects on ability to drive and use machines: Methoxyflurane may have a
minor influence on the ability to drive and use machines. Patients should be advised not to drive or operate machinery if they are
feeling drowsy or dizzy. Undesirable effects: The most common non-serious reactions are CNS type reactions such as dizziness and
somnolence (≥1/100 to